I would not go with Globespan. They have started cancelling flights for Sept as they are not filling their planes. Went last NOv with they and had 9 hr delay on way out and smaller plane on way back. We usually go with Continental via Newark when going out to our villa during the winter season. You could try them.
I have flewn with Aer Lingus to JFK and their plane and flight was very good. I think they class themselves as a scheduled airline.The only thing that puts me off using Aer Lingus is the waiting time at dublin on the way home.

Were do you stay , I live in Renfrew.